In gunnery a gun has to be raised or lowered for range adjustment and turned left or right for azimuth adjustment, all for bringing the gun into the correct position for hitting an identified target, and these operations are referred to herein as "aiming".
In self-propelled, gun-carrying platforms of the kind with which the present invention is concerned, e.g. a combat tank, there exists the need for a swift and reliable communication between the gunner and the commander. In classical arrangements the commander who observes the scene and identifies targets from his own position, communicates vocally with the gunner either directly or through an intercom. In the course of aiming the gunner reports to the commander and/or the commander gives orders to the gunner, and at a suitable moment, the commander gives the fire command. In this classical method valuable time is lost by the bi-directional vocal communication between the gunner and commander. This method is therefore unsatisfactory, in particular with modern gun-carrying, self-propelled mobile platforms with electronic fire control; in such platforms the fire command must be given at a very precise point of time as otherwise the target may be missed.
It has therefore already been proposed to provide systems by which the commander and gunner both follow the aiming of the gun in synchronisation in order to obviate the need for the gunner to report to the commander and when the sighting is right, the commander either gives the order to the gunner or alternatively presses himself a firing actuator. Such an arrangement is disclosed for example in U.S. Pat. No. 4,318,330. In accordance therewith a top-mounted gun of a tank is aimed by means of a fire control system including an optical observation and aiming system controlled by the vehicle gunner after a target, which has been optically sighted by the vehicle commander by means of a stabilized panoramic optical device, has been taken over by the vehicle gunner in his own individually stabilized optical device. After sighting a target the vehicle commander initiates a control signal which causes the actual values of positions of his panoramic optical device to be transmitted to the stabilization control of the gunner's optical device as rated values resulting in the two optical devices being aligned. Thereafter, in response to control signals generated by the gunner, the weapon is aimed at the target as seen through the gunner's optical device, the image of the target as seen by a target television camera fixedly mounted on the weapon is switched to a television monitor in front of the gunner, and then the weapon is finely aimed at the target as seen on the monitor and is fired.
Such sophisticated system is cumbersome, expensive and sensitive to the rough conditions prevailing in operation.
It is the object of the present invention to provide simple yet reliable optical auxiliary means in association with the gunner sighting and range-finding equipment by which the commander can follow the sighting and range-finding operation in synchronization with the gunner.